Stellar tidal streams around nearby spiral galaxies with deep imaging from amateur telescopes (2504.02071v1)

Abstract: Tidal interactions between massive galaxies and their satellites are fundamental processes in a Universe with L-Cold Dark Matter cosmology, redistributing material into faint features that preserve records of past galactic interactions. While stellar streams in the Local Group impressively demonstrate satellite disruption, they do not constitute a statistically significant sample. Constructing a substantial catalog of stellar streams beyond the Local Group remains challenging due to the difficulties in obtaining deep, wide-field images of galaxies. Despite their potential to illuminate dark matter distribution and galaxy formation processes, stellar streams remain underutilized as cosmological probes. The Stellar Tidal Stream Survey (STSS) addresses this observational gap by leveraging amateur telescopes to obtain deep, scientific-grade images of galactic outskirts, capable of building a more statistically meaningful sample of stellar streams. Over the last decade, the STSS has acquired deep (up to surface brightness limit 28.3 mag/arcsec^2 in the r-band), wide-field images of 15 nearby Milky Way analog galaxies using a network of robotic amateur telescopes, avoiding the issues associated with "mosaicing" smaller images taken with a professional telescope. Our survey has revealed a diverse range of previously unreported faint features related to dwarf satellite accretion - including stellar streams, shells, and umbrella-like structures. We discover an ultra-diffuse galaxy (NGC150-UDG1), which shows hints of tidal tails. The STSS demonstrates the suitability of modern amateur telescopes to detect and study faint, diffuse structures in large fields around nearby spiral galaxies. Their economic and accessibility advantages enable larger samples with deep imaging, essential for testing galaxy formation models and constraining the properties of minor merger events in the local Universe.

Stellar Tidal Streams Around Nearby Spiral Galaxies

The paper presents insightful research on the utilization of amateur telescopes in obtaining deep imaging for exploring stellar tidal streams around nearby spiral galaxies. This exploration is pivotal given the cosmological framework of $\Lambda$-Cold Dark Matter ($\Lambda$CDM) that postulates galactic interactions and satellite disruptions as key processes shaping galaxy evolution and distributing matter across the cosmos. The research particularly addresses the observational gap in the construction of a large catalog of stellar streams beyond the Local Group, a challenge exacerbated by the necessity for deep, wide-field imaging capabilities that have traditionally been the domain of professional telescopes.

The Stellar Tidal Stream Survey (STSS) is an ambitious initiative aimed at leveraging amateur telescopes to collect scientific-grade data from the outskirts of galaxies. This approach provides a more statistically significant sample of stellar streams, essential for understanding the redistribution of material due to tidal interactions. Over a decade, the STSS has amassed deep images (up to a surface brightness limit of $\sim$28.3 mag/arcsec$^2$ in the r-band) for fifteen nearby galaxies, similar to the Milky Way, using a network of coordinated robotic amateur telescopes. This methodology circumvents issues like image mosaic artifacts commonly associated with professional telescopes.

The survey has uncovered a diverse range of faint features—stellar streams, shells, and umbrella-like structures—indicative of dwarf satellite accretion. One significant discovery includes an ultra-diffuse galaxy (NGC150-UDG1), identified to have potential tidal tails, which suggests an ongoing or recent accretion event. This network of amateur telescopes provides an economically and technically viable alternative to professional observatories for detecting faint, diffuse structures in galaxy outskirts, facilitating the acquisition of larger statistical samples vital for refining galaxy formation models.

The implications of using modern amateur telescopes are substantial. They present an effective means to paper low surface brightness (LSB) features without the logistical and financial demands associated with professional telescopes. This democratization of deep sky observation not only enriches the data available for cosmological studies but also enhances our understanding of the frequency and properties of minor merger events within the local universe. The ability to detect and analyze these LSB structures has implications for testing and improving models of galaxy halos and their dark matter content.

Future advancements in the field could benefit from the increasing accessibility of high-quality imaging equipment to amateur astronomers, potentially enhancing data collection further exploit these cosmic laboratories. Additionally, collaboration with larger professional observatories to juxtapose findings could lead to more comprehensive models and simulations, aiding in the exploration of the intricate dynamics of galaxy interactions and the underlying dark matter structures.

In conclusion, this research underscores the practicality and efficacy of amateur telescopes in contributing to the field of extragalactic astrophysics. Through the STSS, the paper illuminates the possibilities for expanding our observational horizons and deepening our comprehension of the cosmic processes that govern galaxy evolution and interaction.